lawrence



2 Sheets-Sheet 1.

(No Model.)

L. P. LAWRENCE.

VACUUM BRAKE FOR RAILWAY CARS.

l/VVE/VTOR @WM ZW ATTORNEYS.

Patented Oct. 18, 1887.

W/TA/ESSES. Mz/ZMZ N. PETERS. PhowLhhognpMr. washings", DAC.

2 Sheets-Sheet 2.

(No Model.)

L. P. LAWRENCE.

VACUUM BRAKE FOR RAILWAY CARS.

Patented Oct. 18, 1887.

' l/Vl/E/VTOH Z B NW ATTORNEY! I 1. l .h. 4 t

WIT/H8858 A/JZZM N. PETERS, PholoLltM nphar, Washington. D. Q

UNITED STATES PATENT EEicE.

LOUIS P. LA'W-RENCE, OF PASSAIG, NEW JERSEY, ASSIGNOR TO THE LA\V- RENCE RAILWVAY BRAKE COMPANY, OF NEYV YORK, N. Y.

VACUUM BRAKE FOR RAILWAY- CARS.

SPECIFICATION forming part of Letters Patent No. 371,603, dated October 18, 1887.

Application filed November 4, 1886. Serial No. 117,040. (No model.)

To aZZ whom it may concern.-

Be it known that 1, Louis P. LAWRENoE, of Passaic, in the county of Passaic, State of New Jersey, have invented certain new and useful Improvements in Vacuum -Brakes for Railway-Cars, of which the following is a speciflcation.

This invention relates to certain new and useful improvements in the vacuunrbrake for railway-cars for which Letters Patent have been granted to me under date of June 24, 1884, No. 300,877.

The object of my invention is to improve the construction of the parts and render the brake more effective.

The invention consists in the construction and combination of parts and details, as will be fully described and set forth hereinafter, and finally pointed out in the claims.

In the accompanying drawings, Figure 1 is a side view of a tender provided with my improved vacuum-brake, parts being broken out and others in section. Fig. 2 is an enlarged detail sectional view of the cylinder and piston. Fig. 3 is a detail sectional view of the edge part of the piston and the packing.

Similar letters of reference indicate corresponding parts.

The cylinder A is open at the bottom and closed at the top, and is fastened to the under side of the car or tender B in such a manner that the longitudinal axis of the cylinder is at right angles to the plane of the car-floor. The cylinder is provided with a bottom flange, to which is bolted the flange of the head 0, forming the bottom of the cylinder. A ring, D, of rubber or other suitable flexible material, is provided on the inner and outer rim with a bead, E, preferably made wedge-shaped, as shown in Fig. 2. The outer bead is clamped between the cylinder and piston, and the inner bead is sprung into the corresponding-shaped groove in the thickened edge of the piston F in the cylinder, which piston is of less diameter than the cylinder, so as to permit the flexible material I) to lap, as shown.

The piston F is providedwith a downwardly-projecting piston-rod, G, which is guided in an aperture in the head 0, and directly below the piston the head is provided with an air-tight connection.

enlargement, in which the pulleys H are located, pulleys J being pivoted in slots in the head at each side of the piston-rod. A chain, K, passes under the pulleys J and over the pulleys H, and is connected with the rods L, connected with the brake-levers in the usual manner. The piston is also provided with an upwardly-projecting tubular guide, M, which projects into a tubular projection, N, in the top of the cylinder, said tubular projection being cast integral with the top of said cylinder. A spiral spring, 0, is contained in the tubular guide M, and its end is rested against the bottom of said guide N and the closed end of the tubular projection on the top of the cylinder, which spring serves to press the piston downward. Pipes P, having the usual couplings, are connected with the cylinder and extend along the bottom of the car.

The operation is as follows: \Vhen a vacuum is formed in the top of the cylinder, the piston F is pressed upward and the brakes are pressed on the tires of the wheels; but when the vacuum is destroyed the piston is moved downward, whereby the brakes are released. The edge or rim of the piston does not slide on the inside of'the cylinder, but is always some distance from the same, so that the space between the piston and the cylinder is filled by the packing-ring, which forms an absolutely As the flexible ring does not slide but only laps, and as there is no joint in the packing-ring in the space between the piston and the sides of the cylinder, there is no danger of its cracking or breaking.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. The combination, with a cylinder, ofapiston of less diameter, which piston is provided with a wedge-shaped groove in its rim, and a flexible packing-ring provided with a wedgeshaped bead on its inner and outer edge, the inner wedge-shaped bead being sprung in the wedge-shaped groovein the rim of the piston, and the outer head of the ring being clamped, substantially as shown and described.

2. The con1bination,with a cylinder, A, having a tubular closed projection, N, on its top, of a piston in the cylinder, a tubular guide projecting from the top of the piston into the tubular projection on the top of the cylinder, ton,which ring is also fastened on the sides of a spring in said tubular guide on the top of the cylinder, substantially as shown and dethe piston, and a flexible ring fastened to the scribed. edge of the piston and the sides of the cyl- In testimony that I claim the foregoing as 5 inder, substantially as shown and described. my invention I have signed my name in pres- 15 3. The combination, with a cylinder, of a ence of two subscribing witnesses.

piston in the same, which piston is of less di- LOUIS P. LAWRENCE. ameter than the cylinder, and consists of a Witnesses: 1

single solid piece, and of a ring of flexible ma- MARTIN PETRY, 1o terial held in a groove in the rim of the pis- SIDNEY MANN. 

